// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/i18n/number_formatting.h"

#include <stddef.h>

#include <memory>

#include "base/format_macros.h"
#include "base/i18n/message_formatter.h"
#include "base/lazy_instance.h"
#include "base/logging.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "third_party/icu/source/common/unicode/ustring.h"
#include "third_party/icu/source/i18n/unicode/numfmt.h"

namespace base {

namespace {

    // A simple wrapper around icu::NumberFormat that allows for resetting it
    // (as LazyInstance does not).
    struct NumberFormatWrapper {
        NumberFormatWrapper()
        {
            Reset();
        }

        void Reset()
        {
            // There's no ICU call to destroy a NumberFormat object other than
            // operator delete, so use the default Delete, which calls operator delete.
            // This can cause problems if a different allocator is used by this file
            // than by ICU.
            UErrorCode status = U_ZERO_ERROR;
            number_format.reset(icu::NumberFormat::createInstance(status));
            DCHECK(U_SUCCESS(status));
        }

        std::unique_ptr<icu::NumberFormat> number_format;
    };

    LazyInstance<NumberFormatWrapper> g_number_format_int = LAZY_INSTANCE_INITIALIZER;
    LazyInstance<NumberFormatWrapper> g_number_format_float = LAZY_INSTANCE_INITIALIZER;

} // namespace

string16 FormatNumber(int64_t number)
{
    icu::NumberFormat* number_format = g_number_format_int.Get().number_format.get();

    if (!number_format) {
        // As a fallback, just return the raw number in a string.
        return ASCIIToUTF16(StringPrintf("%" PRId64, number));
    }
    icu::UnicodeString ustr;
    number_format->format(number, ustr);

    return string16(ustr.getBuffer(), static_cast<size_t>(ustr.length()));
}

string16 FormatDouble(double number, int fractional_digits)
{
    icu::NumberFormat* number_format = g_number_format_float.Get().number_format.get();

    if (!number_format) {
        // As a fallback, just return the raw number in a string.
        return ASCIIToUTF16(StringPrintf("%f", number));
    }
    number_format->setMaximumFractionDigits(fractional_digits);
    number_format->setMinimumFractionDigits(fractional_digits);
    icu::UnicodeString ustr;
    number_format->format(number, ustr);

    return string16(ustr.getBuffer(), static_cast<size_t>(ustr.length()));
}

string16 FormatPercent(int number)
{
    return i18n::MessageFormatter::FormatWithNumberedArgs(
        ASCIIToUTF16("{0,number,percent}"), static_cast<double>(number) / 100.0);
}

namespace testing {

    void ResetFormatters()
    {
        g_number_format_int.Get().Reset();
        g_number_format_float.Get().Reset();
    }

} // namespace testing

} // namespace base
